The T.rex was a massive coward – and we have the footage to prove it

It’s over 66 million years ago, and we’re watching a Tyrannosaurus rex devour the carcass of a giant sauropod dinosaur. You definitely wouldn’t want to be nearby, but… something’s different. The T.rex is a monster, sure – but its teeth are not those of the Jurassic Park beast’s giant daggers. It’s looking quite small really, and – strangely – it has lips.

Most importantly, the T.rex is overshadowed by a strange, somewhat elegant creature that resembles a hornbill bird mixed with a lemur. It’s called a Quetzalcoatlus: it’s another giant predator, a pterosaur. And at six metres tall (the size of a giraffe), it’s slightly bigger than the T.rex.

The familiar voice of David Attenborough tells us that this other beast could poke the T.rex’s eyes out with its almost 2m long beak. We don't get to see it try. In a surprising turn of events, the iconic Tyrannosaurus rex – whose name literally comes from the Greek word for ‘absolute ruler’ – backs down.

This is palaeontologist Darren Naish’s favourite scene in the Apple TV+ second season of Prehistoric Planet, out now. We spoke to Naish – the series’ lead palaeontology consultant – about the science behind it.

“Everyone, of course, always thinks of Tyrannosaurus rex as the ultimate predator: a non-stoppable killing machine that just bites other things in half,” he says.

“But no predator behaves that way. Every predator does things to minimise the risk of injury and death to itself.

“There are cases where they will be very conservative behaviourally, almost cowardly. Because it's just not worth getting stabbed in the eye.”

How do scientists know how dinosaurs behaved?

The second season of Prehistoric Planet focuses on interactions between creatures like this one, asking questions like 'What happens when two giant apex predators are competing for the same resource?'

“We answer that question,” says Naish.

But how does he know this is how the dinosaur might act? It's not all guesswork. The answer is based on published research – much of which Naish has been involved in.

Naish tells us that the answer comes from a combination of factors, particularly their anatomy, and the behaviour of living animals that are similar to these extinct ones.

“This is not an imaginary scenario," he argues. "This is entirely backed up by all these different scientific points.”

First, the scientists had to work out how to execute the appearance of the Quetzalcoatlus, which was based on research from 2008 that marked a paradigm shift in how researchers think they were built. It showed that their narrow build, with foldable 9m wings on a leggy body, made them incredibly competent terrestrial predators with the ability to fly.

A more recent study, in 2015, investigated what this build would have meant for interactions with other large predators like the T.rex.

“They've both got strengths. They've both got possible weaknesses,” said Naish. “But we’ve argued that the Tyrannosaurus would have second thoughts when confronted with such a tall predator.

“In the sequence, there is actually more than one of these animals, too, because there is evidence for social behaviour in them.”